Disclosed herein is a scorotron apparatus for charging a photoconductor in a printing system.
Presently, in a xerographic printing process, a scorotron is used to charge a photoreceptor so that an electrostatic latent image may be applied to the photoreceptor. The electrostatic latent image is developed to form a visible image, which is then transferred to media to generate an image on the media.
For example, a scorotron charges the photoreceptor by driving charged particles onto it. The charged particles are generated by the scorotron by creating an electric potential using a conductor having points or a conductor with a high curvature, such as a narrow diameter wire. The conductor concentrates the electric field and causes it to split the molecules in the air to distribute electrons off of the molecules in the air. The electrons are drawn by the electric field in one direction and the ions go in the other direction. A negative polarity can be used to cause the electrons and negatively charged ions to go toward the photoreceptor and the positive ions can be neutralized through a high voltage connection. Electrical potentials of hundreds or thousands of volts can be applied to drive charged particles to the photoreceptor to prepare the photoreceptor for image production. A laser or other device can then be used to apply the image to the photoreceptor and the image can be transferred to media.
A charging device such as a scorotron is necessary for charging the photoreceptor in such a process. A scorotron is relatively complex and expensive to assemble. Furthermore, a scorotron takes up precious space in a printing device. A pin array can be used in a scorotron to increase the scorotron efficiency. The pin array also makes assembly of the scorotron more complex and costly.
Thus there is a need for an improved apparatus useful in charging a photoconductor for printing.